双链表的每个结点包括两个指针域。其中rlink指向结点的后继，llink指向结点的前驱。如果要在p所指结点后插入q所指的新结点，下列哪一个操作序列是正确的
A．p↑.rlink↑.llink:=q; P↑.rlink:=q;q↑.llink:=p; q↑.rlink:=p↑.rlink;
B．p↑.llink↑.rlink:=q; p↑.l1ink:=q;q↑.rlink:=p;q↑.llink:=p↑.llink;
C．q↑.llink:=p;q↑.rlink:=p↑.rlink;p↑.rlink↑.llink:=q;p↑.rlink:=q;
D．q↑.rlink:=p;q↑.llink:=p↑.llink;p↑.llink↑.rlink:=q;p↑.llink:=q;
